Diesel fuel oil



nite tatcs The present application relates to fuel oils having improvedcombustion efiiciency.

The term fuel oil in general comprises all liquid hydrocarbons used asfuels for burners and furnaces and the like, or as fuels for dieselengines, and includes both residual oils and distillate oils such as gasoil. The fuel oil may, for example, have a Luchaire flash point above 60C.

It is generally necessary to improve the properties, in particular thecombustion efficiency, of fuel oils. It has been observed, particularlyin diesel engines, that when the quantity of fuel injected is increased,smoke, increasing with the quantity of fuel injected, appears in theexhaust gases. This is due to the incomplete combustion of the fuelwhich decreases the combustion efiiciency of the engine and also causesengine fouling.

It has now been discovered that fuel oils of improved combustionefficiency are obtained when the fuel oil contains a minor proportion ofan oil-soluble compound formed by reacting an organic base, or analkylene oxide containing from 2 to 6 carbon atoms, with an organicderivative of phosphoric acid having the general formula:

wherein X represents oxygen or sulphur, R and R represent alkyl orsubstituted alkyl radicals containing from 2 to 20 carbon atoms,preferably 8 to 14 carbon atoms.

The oil-soluble organic phosphorus compounds of the present inventionare self-dispersing in fuel oils and are derivatives of phosphoric acidin which an acid hydrogen is combined with:

(1) An organic base such as an amine to form a salt in which Xrepresents oxygen or sulphur, R" and R' may be alkyl radicals having forpreference from 2 to 20 atoms, better still 8 to 14 atoms of carbon.These radicals may or may not have substituent groups such as OH, NH;,,SH, CN etc.; R' may be an alkyl radical having for preference from 4 to18 and better still from 6 to 12 carbon atoms.

(2) An alkylene oxide having for preference from 2 to 6 carbon atoms, toyield in the case of ethylene oxide the derivatives complying with thegeneral formula:

0 (CHz-CHa-O) H X=P-OR" in which X, R and R" have the same meaning as inthe previous formula and n represents a whole number.

According to the invention, the amines used may be of the straight orbranched chain type, primary or secondary, mono-amines or polyamines,amido-arnines or ethanolamines.

The quantity of organic derivative of phosphoric acid to be added to thefuel oil is for the preference between 3,074,336 Patented Jan. 22, 1963ice 0.005 and 5% better still between 0.05 and 1% by weight in relationto the fuel oil.

This organic derivative of phosphoric acid is particularly'suitable forimproving gas oils, domestic fuel oils, light and heavy fuel 'oils, i;e.light hydrocarbons having aLuchairefiash point above 60 C.

The following examples given by way of explanation will better show thescope and importance of the invention.

The tests 'were carried out with a diesel engine of General Motors (GM371) possessing the following characteristics:

Number of cylinders 3.

.Bore in mm 108 (4% inches). Stroke in mm. 127 (5 inches). Cylindercapacity in cc. 3474 (212 cubic inches). Temperature of water C.

Temperature of oil 107 C.

Speed 1200 r.p.m.

Smoke measurements at the exhaust'have'been carried out by means of thesmoke meter known by the name of the Von Brand Smoke-meter. Thisapparatus makes it possible to effect the measurement of the smokecontained in the exhaust'gases, by causing the latter to pass through apaper screen unwinding at constant rate. The intensity of the spot isobtained by interpolation between two standards (one white and the otherblack), by measuring the percentage of light reflected with the aid of aphoto-reflecto-meter.

By running the diesel engine with a determined output and feeding itwith a gas oil with or without additive, the following characteristicswere measured,

and the following calculation was made:

Consumption of gas oil with additive consumption gas oil withoutadditive Consumption of fuel oil Without additive EXAMPLE I With the useof a gas oil having the following characteristics:

Density at 15 C. 0.857 Engler viscosity at 20 C. 1.43 Sulphur 1% thefollowing results were obtained, using as additive according to theinvention the product resulting from the neutralization ofdilaurophosphoric acid with octylamine in the proportion of 0.6 g. perkg. of gas oil.

Cetane number Table 1 Output in H.P.

Datum Gas Oil:

I 13. 5 15.5 16. 5 l9. 5 24. 5 28. 5 34. 5 C 9. 56 10. 28 11.01 11. 6912. 53 12. 98 13. 57 t, C 238 253 267 282 297 309 321 Gas Oil additives:

9. 44 10. 17 10.86 11. 59 12. 44 12.87 13. 53 AC -1. 22 1. 04 -l. 30 0.0. 68 0. 83 0. 25 t, 0-.-. 236 250 264 280 296 305 318 3 These resultsshow that the application of the additive according to the inventionmakes it possible to: (1) Obtain less smoke for a given output. (2)Obtain more power for a given smoke index. (3) Lessen consumption.

EXAMPLE II Using the same gas-oil as in Example 'I, the followingresults were obtained, using as additive according to the inventionethoxy-dilaurophosphoric acid with 6 molecules of ethylene oxide in theproportion of 0.6 g. per kg. gas

It is obvious that this invention has only been described by way ofexplanation and in no sense restrictively.

What is claimed is: 1. An improved diesel fuel oil compositioncontaining between 0.005 and 5.0 weight percent of an oil solubleorganic phosphorus additive having the formula:

wherein X is selected from the group of oxygen and sulfur, R and R" arealkyl radicals of from 2 to 20 carbon atoms, and n is a whole numberfrom 2 to 6, said compound enhancing the combustion eificiency of saiddiesel oil.

2. A diesel fuel oil composition as defined in claim 1 wherein said oilsoluble additive is added in an amount between 0.05 and 1.0 weightpercent.

3. A diesel fuel oil composition as defined in claim 1 wherein said X isoxygen, R and R" have from 8 to 14 carbon atoms, and n is 6.

4. A diesel fuel oil composition as defined in claim 1 wherein saiddiesel oil has a Luchaire flash point above C.

5. A process of operating a diesel engine, which process comprisesadding to a diesel fuel oil between 0.005 and 5.0 weight percent of anoil soluble organic phosphorus additive having the formula:

wherein X is selected from the group of oxygen and sulfur, R and R" arealkyl radicals of from 2 to 20 carbon atoms, and n is a whole numberfrom 2 to 6, and combusting said fuel in said engine, thereby enhancingthe combustion efliciency and reducing the tendency of said engine tosmoke.

6. A process as defined by claim 5 wherein said oil soluble additive isadded in an amount between 0.05 and 1.0 weight percent.

7. A process as defined by claim 5 wherein said X is oxygen, R and R"have from 8 to 14 carbon atoms, and n is 6.

8. A process as defined by claim 5 wherein said fuel oil is a diesel oilhaving a Luchaire flash point above 60 C.

References Cited in the file of this patent UNITED STATES PATENTS2,335,953 McCracken et a1. Dec. 7, 1943 2,602,049 Smith et al July 1,1952 2,793,945 Walker et al. May 28, 1957 2,841,126 Cantrell et a1. July1, 1958 2,905,542 Gottshall et al Sept. 22, 1959 2,979,523 Cantrell eta1 Apr. 11, 1961

5. A PROCESS OF OPERATING A DIESEL ENGINE, WHICH PROCESS COMPRISESADDING TO A DIESEL FUEL OIL BETWEEN 0.005 AND 5.0 WEIGHT PERCENT OF ANOIL SOLUBLE ORGANIC PHOSPHORUS ADDITIVE HAVING THE FORMULA: